It is already known to use pressure-reducing means in the coupling part of a quick coupling. By means of the pressure-reducing means it is possible to reduce pressure in the coupling part by leading off a small amount of media (for example hydraulic oil, other liquid, gas etc.) to the end face of the coupling part. The coupling together of the coupling parts of the quick coupling is facilitated in this way. It is also known to arrange pressure-reducing means in both coupling parts.
It is also known to use pressure-reducing means in a coupling part which operates with a double shut-off for the media pressure, in which a first shut-off function first shuts off the pressure in a first uncoupling stage of the coupling parts, and a second shut-off function, which complements the first shut-off function, is established in the final stage of the uncoupling procedure.
In the case of coupling arrangements of the type in question, there is desirable to use the same coupling part construction regardless of the situation in which it is employed. Sometimes coupling is to be carried out with pressure in the female part and sometimes with pressure in the male part. Coupling together may also be carried out with pressure in both coupling parts and with a pressureless condition in both coupling parts.
A further requirement is that the coupling and uncoupling should be carried out in a manner completely free from spillage or leakage. The basic problem is therefore to be able to couple up/disconnect pressures, even high pressures, in a leakage-free manner in different situations and with different system constructions in which one and the same quick-coupling type is to be used.
For this purpose, a pressure-reducing concept is required, which has an all-round application and which can be used according to the modular concept in the quick-coupling part construction. One or both coupling parts are to be provided with the pressure-reducing means so that coupling constructions which are tailor-made for different application situations can be obtained.
In this context it is crucial that the pressure-reducing means can operate with a technical principle otherwise uncritical for the pressure-reducing function and the quick-coupling function. The pressure-reducing means will consist of parts which can be easily assembled and which can be applied easily in the coupling part in question, so that the coupling part does not need to have an essentially different construction compared to a coupling part without pressure-reducing means.
It is important that there should be complete freedom from leakage, which means, among other thing, that the media which has been led off cannot be allowed to reach the end face of the coupling part.